x86/xen: resume timer irqs early
[linux/fpc-iii.git] / kernel / power / hibernate.c
blob0121dab83f43d82ddfb620f7423d6c9728f8b01b
1 /*
2 * kernel/power/hibernate.c - Hibernation (a.k.a suspend-to-disk) support.
4 * Copyright (c) 2003 Patrick Mochel
5 * Copyright (c) 2003 Open Source Development Lab
6 * Copyright (c) 2004 Pavel Machek <pavel@ucw.cz>
7 * Copyright (c) 2009 Rafael J. Wysocki, Novell Inc.
8 * Copyright (C) 2012 Bojan Smojver <bojan@rexursive.com>
10 * This file is released under the GPLv2.
13 #include <linux/export.h>
14 #include <linux/suspend.h>
15 #include <linux/syscalls.h>
16 #include <linux/reboot.h>
17 #include <linux/string.h>
18 #include <linux/device.h>
19 #include <linux/async.h>
20 #include <linux/delay.h>
21 #include <linux/fs.h>
22 #include <linux/mount.h>
23 #include <linux/pm.h>
24 #include <linux/console.h>
25 #include <linux/cpu.h>
26 #include <linux/freezer.h>
27 #include <linux/gfp.h>
28 #include <linux/syscore_ops.h>
29 #include <linux/ctype.h>
30 #include <linux/genhd.h>
32 #include "power.h"
35 static int nocompress;
36 static int noresume;
37 static int resume_wait;
38 static int resume_delay;
39 static char resume_file[256] = CONFIG_PM_STD_PARTITION;
40 dev_t swsusp_resume_device;
41 sector_t swsusp_resume_block;
42 __visible int in_suspend __nosavedata;
44 enum {
45 HIBERNATION_INVALID,
46 HIBERNATION_PLATFORM,
47 HIBERNATION_SHUTDOWN,
48 HIBERNATION_REBOOT,
49 #ifdef CONFIG_SUSPEND
50 HIBERNATION_SUSPEND,
51 #endif
52 /* keep last */
53 __HIBERNATION_AFTER_LAST
55 #define HIBERNATION_MAX (__HIBERNATION_AFTER_LAST-1)
56 #define HIBERNATION_FIRST (HIBERNATION_INVALID + 1)
58 static int hibernation_mode = HIBERNATION_SHUTDOWN;
60 bool freezer_test_done;
62 static const struct platform_hibernation_ops *hibernation_ops;
64 /**
65 * hibernation_set_ops - Set the global hibernate operations.
66 * @ops: Hibernation operations to use in subsequent hibernation transitions.
68 void hibernation_set_ops(const struct platform_hibernation_ops *ops)
70 if (ops && !(ops->begin && ops->end && ops->pre_snapshot
71 && ops->prepare && ops->finish && ops->enter && ops->pre_restore
72 && ops->restore_cleanup && ops->leave)) {
73 WARN_ON(1);
74 return;
76 lock_system_sleep();
77 hibernation_ops = ops;
78 if (ops)
79 hibernation_mode = HIBERNATION_PLATFORM;
80 else if (hibernation_mode == HIBERNATION_PLATFORM)
81 hibernation_mode = HIBERNATION_SHUTDOWN;
83 unlock_system_sleep();
86 static bool entering_platform_hibernation;
88 bool system_entering_hibernation(void)
90 return entering_platform_hibernation;
92 EXPORT_SYMBOL(system_entering_hibernation);
94 #ifdef CONFIG_PM_DEBUG
95 static void hibernation_debug_sleep(void)
97 printk(KERN_INFO "hibernation debug: Waiting for 5 seconds.\n");
98 mdelay(5000);
101 static int hibernation_test(int level)
103 if (pm_test_level == level) {
104 hibernation_debug_sleep();
105 return 1;
107 return 0;
109 #else /* !CONFIG_PM_DEBUG */
110 static int hibernation_test(int level) { return 0; }
111 #endif /* !CONFIG_PM_DEBUG */
114 * platform_begin - Call platform to start hibernation.
115 * @platform_mode: Whether or not to use the platform driver.
117 static int platform_begin(int platform_mode)
119 return (platform_mode && hibernation_ops) ?
120 hibernation_ops->begin() : 0;
124 * platform_end - Call platform to finish transition to the working state.
125 * @platform_mode: Whether or not to use the platform driver.
127 static void platform_end(int platform_mode)
129 if (platform_mode && hibernation_ops)
130 hibernation_ops->end();
134 * platform_pre_snapshot - Call platform to prepare the machine for hibernation.
135 * @platform_mode: Whether or not to use the platform driver.
137 * Use the platform driver to prepare the system for creating a hibernate image,
138 * if so configured, and return an error code if that fails.
141 static int platform_pre_snapshot(int platform_mode)
143 return (platform_mode && hibernation_ops) ?
144 hibernation_ops->pre_snapshot() : 0;
148 * platform_leave - Call platform to prepare a transition to the working state.
149 * @platform_mode: Whether or not to use the platform driver.
151 * Use the platform driver prepare to prepare the machine for switching to the
152 * normal mode of operation.
154 * This routine is called on one CPU with interrupts disabled.
156 static void platform_leave(int platform_mode)
158 if (platform_mode && hibernation_ops)
159 hibernation_ops->leave();
163 * platform_finish - Call platform to switch the system to the working state.
164 * @platform_mode: Whether or not to use the platform driver.
166 * Use the platform driver to switch the machine to the normal mode of
167 * operation.
169 * This routine must be called after platform_prepare().
171 static void platform_finish(int platform_mode)
173 if (platform_mode && hibernation_ops)
174 hibernation_ops->finish();
178 * platform_pre_restore - Prepare for hibernate image restoration.
179 * @platform_mode: Whether or not to use the platform driver.
181 * Use the platform driver to prepare the system for resume from a hibernation
182 * image.
184 * If the restore fails after this function has been called,
185 * platform_restore_cleanup() must be called.
187 static int platform_pre_restore(int platform_mode)
189 return (platform_mode && hibernation_ops) ?
190 hibernation_ops->pre_restore() : 0;
194 * platform_restore_cleanup - Switch to the working state after failing restore.
195 * @platform_mode: Whether or not to use the platform driver.
197 * Use the platform driver to switch the system to the normal mode of operation
198 * after a failing restore.
200 * If platform_pre_restore() has been called before the failing restore, this
201 * function must be called too, regardless of the result of
202 * platform_pre_restore().
204 static void platform_restore_cleanup(int platform_mode)
206 if (platform_mode && hibernation_ops)
207 hibernation_ops->restore_cleanup();
211 * platform_recover - Recover from a failure to suspend devices.
212 * @platform_mode: Whether or not to use the platform driver.
214 static void platform_recover(int platform_mode)
216 if (platform_mode && hibernation_ops && hibernation_ops->recover)
217 hibernation_ops->recover();
221 * swsusp_show_speed - Print time elapsed between two events during hibernation.
222 * @start: Starting event.
223 * @stop: Final event.
224 * @nr_pages: Number of memory pages processed between @start and @stop.
225 * @msg: Additional diagnostic message to print.
227 void swsusp_show_speed(struct timeval *start, struct timeval *stop,
228 unsigned nr_pages, char *msg)
230 s64 elapsed_centisecs64;
231 int centisecs;
232 int k;
233 int kps;
235 elapsed_centisecs64 = timeval_to_ns(stop) - timeval_to_ns(start);
236 do_div(elapsed_centisecs64, NSEC_PER_SEC / 100);
237 centisecs = elapsed_centisecs64;
238 if (centisecs == 0)
239 centisecs = 1; /* avoid div-by-zero */
240 k = nr_pages * (PAGE_SIZE / 1024);
241 kps = (k * 100) / centisecs;
242 printk(KERN_INFO "PM: %s %d kbytes in %d.%02d seconds (%d.%02d MB/s)\n",
243 msg, k,
244 centisecs / 100, centisecs % 100,
245 kps / 1000, (kps % 1000) / 10);
249 * create_image - Create a hibernation image.
250 * @platform_mode: Whether or not to use the platform driver.
252 * Execute device drivers' "late" and "noirq" freeze callbacks, create a
253 * hibernation image and run the drivers' "noirq" and "early" thaw callbacks.
255 * Control reappears in this routine after the subsequent restore.
257 static int create_image(int platform_mode)
259 int error;
261 error = dpm_suspend_end(PMSG_FREEZE);
262 if (error) {
263 printk(KERN_ERR "PM: Some devices failed to power down, "
264 "aborting hibernation\n");
265 return error;
268 error = platform_pre_snapshot(platform_mode);
269 if (error || hibernation_test(TEST_PLATFORM))
270 goto Platform_finish;
272 error = disable_nonboot_cpus();
273 if (error || hibernation_test(TEST_CPUS))
274 goto Enable_cpus;
276 local_irq_disable();
278 error = syscore_suspend();
279 if (error) {
280 printk(KERN_ERR "PM: Some system devices failed to power down, "
281 "aborting hibernation\n");
282 goto Enable_irqs;
285 if (hibernation_test(TEST_CORE) || pm_wakeup_pending())
286 goto Power_up;
288 in_suspend = 1;
289 save_processor_state();
290 error = swsusp_arch_suspend();
291 if (error)
292 printk(KERN_ERR "PM: Error %d creating hibernation image\n",
293 error);
294 /* Restore control flow magically appears here */
295 restore_processor_state();
296 if (!in_suspend) {
297 events_check_enabled = false;
298 platform_leave(platform_mode);
301 Power_up:
302 syscore_resume();
304 Enable_irqs:
305 local_irq_enable();
307 Enable_cpus:
308 enable_nonboot_cpus();
310 Platform_finish:
311 platform_finish(platform_mode);
313 dpm_resume_start(in_suspend ?
314 (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
316 return error;
320 * hibernation_snapshot - Quiesce devices and create a hibernation image.
321 * @platform_mode: If set, use platform driver to prepare for the transition.
323 * This routine must be called with pm_mutex held.
325 int hibernation_snapshot(int platform_mode)
327 pm_message_t msg;
328 int error;
330 error = platform_begin(platform_mode);
331 if (error)
332 goto Close;
334 /* Preallocate image memory before shutting down devices. */
335 error = hibernate_preallocate_memory();
336 if (error)
337 goto Close;
339 error = freeze_kernel_threads();
340 if (error)
341 goto Cleanup;
343 if (hibernation_test(TEST_FREEZER)) {
346 * Indicate to the caller that we are returning due to a
347 * successful freezer test.
349 freezer_test_done = true;
350 goto Thaw;
353 error = dpm_prepare(PMSG_FREEZE);
354 if (error) {
355 dpm_complete(PMSG_RECOVER);
356 goto Thaw;
359 suspend_console();
360 ftrace_stop();
361 pm_restrict_gfp_mask();
363 error = dpm_suspend(PMSG_FREEZE);
365 if (error || hibernation_test(TEST_DEVICES))
366 platform_recover(platform_mode);
367 else
368 error = create_image(platform_mode);
371 * In the case that we call create_image() above, the control
372 * returns here (1) after the image has been created or the
373 * image creation has failed and (2) after a successful restore.
376 /* We may need to release the preallocated image pages here. */
377 if (error || !in_suspend)
378 swsusp_free();
380 msg = in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE;
381 dpm_resume(msg);
383 if (error || !in_suspend)
384 pm_restore_gfp_mask();
386 ftrace_start();
387 resume_console();
388 dpm_complete(msg);
390 Close:
391 platform_end(platform_mode);
392 return error;
394 Thaw:
395 thaw_kernel_threads();
396 Cleanup:
397 swsusp_free();
398 goto Close;
402 * resume_target_kernel - Restore system state from a hibernation image.
403 * @platform_mode: Whether or not to use the platform driver.
405 * Execute device drivers' "noirq" and "late" freeze callbacks, restore the
406 * contents of highmem that have not been restored yet from the image and run
407 * the low-level code that will restore the remaining contents of memory and
408 * switch to the just restored target kernel.
410 static int resume_target_kernel(bool platform_mode)
412 int error;
414 error = dpm_suspend_end(PMSG_QUIESCE);
415 if (error) {
416 printk(KERN_ERR "PM: Some devices failed to power down, "
417 "aborting resume\n");
418 return error;
421 error = platform_pre_restore(platform_mode);
422 if (error)
423 goto Cleanup;
425 error = disable_nonboot_cpus();
426 if (error)
427 goto Enable_cpus;
429 local_irq_disable();
431 error = syscore_suspend();
432 if (error)
433 goto Enable_irqs;
435 save_processor_state();
436 error = restore_highmem();
437 if (!error) {
438 error = swsusp_arch_resume();
440 * The code below is only ever reached in case of a failure.
441 * Otherwise, execution continues at the place where
442 * swsusp_arch_suspend() was called.
444 BUG_ON(!error);
446 * This call to restore_highmem() reverts the changes made by
447 * the previous one.
449 restore_highmem();
452 * The only reason why swsusp_arch_resume() can fail is memory being
453 * very tight, so we have to free it as soon as we can to avoid
454 * subsequent failures.
456 swsusp_free();
457 restore_processor_state();
458 touch_softlockup_watchdog();
460 syscore_resume();
462 Enable_irqs:
463 local_irq_enable();
465 Enable_cpus:
466 enable_nonboot_cpus();
468 Cleanup:
469 platform_restore_cleanup(platform_mode);
471 dpm_resume_start(PMSG_RECOVER);
473 return error;
477 * hibernation_restore - Quiesce devices and restore from a hibernation image.
478 * @platform_mode: If set, use platform driver to prepare for the transition.
480 * This routine must be called with pm_mutex held. If it is successful, control
481 * reappears in the restored target kernel in hibernation_snapshot().
483 int hibernation_restore(int platform_mode)
485 int error;
487 pm_prepare_console();
488 suspend_console();
489 ftrace_stop();
490 pm_restrict_gfp_mask();
491 error = dpm_suspend_start(PMSG_QUIESCE);
492 if (!error) {
493 error = resume_target_kernel(platform_mode);
494 dpm_resume_end(PMSG_RECOVER);
496 pm_restore_gfp_mask();
497 ftrace_start();
498 resume_console();
499 pm_restore_console();
500 return error;
504 * hibernation_platform_enter - Power off the system using the platform driver.
506 int hibernation_platform_enter(void)
508 int error;
510 if (!hibernation_ops)
511 return -ENOSYS;
514 * We have cancelled the power transition by running
515 * hibernation_ops->finish() before saving the image, so we should let
516 * the firmware know that we're going to enter the sleep state after all
518 error = hibernation_ops->begin();
519 if (error)
520 goto Close;
522 entering_platform_hibernation = true;
523 suspend_console();
524 ftrace_stop();
525 error = dpm_suspend_start(PMSG_HIBERNATE);
526 if (error) {
527 if (hibernation_ops->recover)
528 hibernation_ops->recover();
529 goto Resume_devices;
532 error = dpm_suspend_end(PMSG_HIBERNATE);
533 if (error)
534 goto Resume_devices;
536 error = hibernation_ops->prepare();
537 if (error)
538 goto Platform_finish;
540 error = disable_nonboot_cpus();
541 if (error)
542 goto Platform_finish;
544 local_irq_disable();
545 syscore_suspend();
546 if (pm_wakeup_pending()) {
547 error = -EAGAIN;
548 goto Power_up;
551 hibernation_ops->enter();
552 /* We should never get here */
553 while (1);
555 Power_up:
556 syscore_resume();
557 local_irq_enable();
558 enable_nonboot_cpus();
560 Platform_finish:
561 hibernation_ops->finish();
563 dpm_resume_start(PMSG_RESTORE);
565 Resume_devices:
566 entering_platform_hibernation = false;
567 dpm_resume_end(PMSG_RESTORE);
568 ftrace_start();
569 resume_console();
571 Close:
572 hibernation_ops->end();
574 return error;
578 * power_down - Shut the machine down for hibernation.
580 * Use the platform driver, if configured, to put the system into the sleep
581 * state corresponding to hibernation, or try to power it off or reboot,
582 * depending on the value of hibernation_mode.
584 static void power_down(void)
586 #ifdef CONFIG_SUSPEND
587 int error;
588 #endif
590 switch (hibernation_mode) {
591 case HIBERNATION_REBOOT:
592 kernel_restart(NULL);
593 break;
594 case HIBERNATION_PLATFORM:
595 hibernation_platform_enter();
596 case HIBERNATION_SHUTDOWN:
597 kernel_power_off();
598 break;
599 #ifdef CONFIG_SUSPEND
600 case HIBERNATION_SUSPEND:
601 error = suspend_devices_and_enter(PM_SUSPEND_MEM);
602 if (error) {
603 if (hibernation_ops)
604 hibernation_mode = HIBERNATION_PLATFORM;
605 else
606 hibernation_mode = HIBERNATION_SHUTDOWN;
607 power_down();
610 * Restore swap signature.
612 error = swsusp_unmark();
613 if (error)
614 printk(KERN_ERR "PM: Swap will be unusable! "
615 "Try swapon -a.\n");
616 return;
617 #endif
619 kernel_halt();
621 * Valid image is on the disk, if we continue we risk serious data
622 * corruption after resume.
624 printk(KERN_CRIT "PM: Please power down manually\n");
625 while(1);
629 * hibernate - Carry out system hibernation, including saving the image.
631 int hibernate(void)
633 int error;
635 lock_system_sleep();
636 /* The snapshot device should not be opened while we're running */
637 if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
638 error = -EBUSY;
639 goto Unlock;
642 pm_prepare_console();
643 error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
644 if (error)
645 goto Exit;
647 printk(KERN_INFO "PM: Syncing filesystems ... ");
648 sys_sync();
649 printk("done.\n");
651 error = freeze_processes();
652 if (error)
653 goto Exit;
655 lock_device_hotplug();
656 /* Allocate memory management structures */
657 error = create_basic_memory_bitmaps();
658 if (error)
659 goto Thaw;
661 error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
662 if (error || freezer_test_done)
663 goto Free_bitmaps;
665 if (in_suspend) {
666 unsigned int flags = 0;
668 if (hibernation_mode == HIBERNATION_PLATFORM)
669 flags |= SF_PLATFORM_MODE;
670 if (nocompress)
671 flags |= SF_NOCOMPRESS_MODE;
672 else
673 flags |= SF_CRC32_MODE;
675 pr_debug("PM: writing image.\n");
676 error = swsusp_write(flags);
677 swsusp_free();
678 if (!error)
679 power_down();
680 in_suspend = 0;
681 pm_restore_gfp_mask();
682 } else {
683 pr_debug("PM: Image restored successfully.\n");
686 Free_bitmaps:
687 free_basic_memory_bitmaps();
688 Thaw:
689 unlock_device_hotplug();
690 thaw_processes();
692 /* Don't bother checking whether freezer_test_done is true */
693 freezer_test_done = false;
694 Exit:
695 pm_notifier_call_chain(PM_POST_HIBERNATION);
696 pm_restore_console();
697 atomic_inc(&snapshot_device_available);
698 Unlock:
699 unlock_system_sleep();
700 return error;
705 * software_resume - Resume from a saved hibernation image.
707 * This routine is called as a late initcall, when all devices have been
708 * discovered and initialized already.
710 * The image reading code is called to see if there is a hibernation image
711 * available for reading. If that is the case, devices are quiesced and the
712 * contents of memory is restored from the saved image.
714 * If this is successful, control reappears in the restored target kernel in
715 * hibernation_snaphot() which returns to hibernate(). Otherwise, the routine
716 * attempts to recover gracefully and make the kernel return to the normal mode
717 * of operation.
719 static int software_resume(void)
721 int error;
722 unsigned int flags;
725 * If the user said "noresume".. bail out early.
727 if (noresume)
728 return 0;
731 * name_to_dev_t() below takes a sysfs buffer mutex when sysfs
732 * is configured into the kernel. Since the regular hibernate
733 * trigger path is via sysfs which takes a buffer mutex before
734 * calling hibernate functions (which take pm_mutex) this can
735 * cause lockdep to complain about a possible ABBA deadlock
736 * which cannot happen since we're in the boot code here and
737 * sysfs can't be invoked yet. Therefore, we use a subclass
738 * here to avoid lockdep complaining.
740 mutex_lock_nested(&pm_mutex, SINGLE_DEPTH_NESTING);
742 if (swsusp_resume_device)
743 goto Check_image;
745 if (!strlen(resume_file)) {
746 error = -ENOENT;
747 goto Unlock;
750 pr_debug("PM: Checking hibernation image partition %s\n", resume_file);
752 if (resume_delay) {
753 printk(KERN_INFO "Waiting %dsec before reading resume device...\n",
754 resume_delay);
755 ssleep(resume_delay);
758 /* Check if the device is there */
759 swsusp_resume_device = name_to_dev_t(resume_file);
762 * name_to_dev_t is ineffective to verify parition if resume_file is in
763 * integer format. (e.g. major:minor)
765 if (isdigit(resume_file[0]) && resume_wait) {
766 int partno;
767 while (!get_gendisk(swsusp_resume_device, &partno))
768 msleep(10);
771 if (!swsusp_resume_device) {
773 * Some device discovery might still be in progress; we need
774 * to wait for this to finish.
776 wait_for_device_probe();
778 if (resume_wait) {
779 while ((swsusp_resume_device = name_to_dev_t(resume_file)) == 0)
780 msleep(10);
781 async_synchronize_full();
784 swsusp_resume_device = name_to_dev_t(resume_file);
785 if (!swsusp_resume_device) {
786 error = -ENODEV;
787 goto Unlock;
791 Check_image:
792 pr_debug("PM: Hibernation image partition %d:%d present\n",
793 MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
795 pr_debug("PM: Looking for hibernation image.\n");
796 error = swsusp_check();
797 if (error)
798 goto Unlock;
800 /* The snapshot device should not be opened while we're running */
801 if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
802 error = -EBUSY;
803 swsusp_close(FMODE_READ);
804 goto Unlock;
807 pm_prepare_console();
808 error = pm_notifier_call_chain(PM_RESTORE_PREPARE);
809 if (error)
810 goto Close_Finish;
812 pr_debug("PM: Preparing processes for restore.\n");
813 error = freeze_processes();
814 if (error)
815 goto Close_Finish;
817 pr_debug("PM: Loading hibernation image.\n");
819 lock_device_hotplug();
820 error = create_basic_memory_bitmaps();
821 if (error)
822 goto Thaw;
824 error = swsusp_read(&flags);
825 swsusp_close(FMODE_READ);
826 if (!error)
827 hibernation_restore(flags & SF_PLATFORM_MODE);
829 printk(KERN_ERR "PM: Failed to load hibernation image, recovering.\n");
830 swsusp_free();
831 free_basic_memory_bitmaps();
832 Thaw:
833 unlock_device_hotplug();
834 thaw_processes();
835 Finish:
836 pm_notifier_call_chain(PM_POST_RESTORE);
837 pm_restore_console();
838 atomic_inc(&snapshot_device_available);
839 /* For success case, the suspend path will release the lock */
840 Unlock:
841 mutex_unlock(&pm_mutex);
842 pr_debug("PM: Hibernation image not present or could not be loaded.\n");
843 return error;
844 Close_Finish:
845 swsusp_close(FMODE_READ);
846 goto Finish;
849 late_initcall_sync(software_resume);
852 static const char * const hibernation_modes[] = {
853 [HIBERNATION_PLATFORM] = "platform",
854 [HIBERNATION_SHUTDOWN] = "shutdown",
855 [HIBERNATION_REBOOT] = "reboot",
856 #ifdef CONFIG_SUSPEND
857 [HIBERNATION_SUSPEND] = "suspend",
858 #endif
862 * /sys/power/disk - Control hibernation mode.
864 * Hibernation can be handled in several ways. There are a few different ways
865 * to put the system into the sleep state: using the platform driver (e.g. ACPI
866 * or other hibernation_ops), powering it off or rebooting it (for testing
867 * mostly).
869 * The sysfs file /sys/power/disk provides an interface for selecting the
870 * hibernation mode to use. Reading from this file causes the available modes
871 * to be printed. There are 3 modes that can be supported:
873 * 'platform'
874 * 'shutdown'
875 * 'reboot'
877 * If a platform hibernation driver is in use, 'platform' will be supported
878 * and will be used by default. Otherwise, 'shutdown' will be used by default.
879 * The selected option (i.e. the one corresponding to the current value of
880 * hibernation_mode) is enclosed by a square bracket.
882 * To select a given hibernation mode it is necessary to write the mode's
883 * string representation (as returned by reading from /sys/power/disk) back
884 * into /sys/power/disk.
887 static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
888 char *buf)
890 int i;
891 char *start = buf;
893 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
894 if (!hibernation_modes[i])
895 continue;
896 switch (i) {
897 case HIBERNATION_SHUTDOWN:
898 case HIBERNATION_REBOOT:
899 #ifdef CONFIG_SUSPEND
900 case HIBERNATION_SUSPEND:
901 #endif
902 break;
903 case HIBERNATION_PLATFORM:
904 if (hibernation_ops)
905 break;
906 /* not a valid mode, continue with loop */
907 continue;
909 if (i == hibernation_mode)
910 buf += sprintf(buf, "[%s] ", hibernation_modes[i]);
911 else
912 buf += sprintf(buf, "%s ", hibernation_modes[i]);
914 buf += sprintf(buf, "\n");
915 return buf-start;
918 static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
919 const char *buf, size_t n)
921 int error = 0;
922 int i;
923 int len;
924 char *p;
925 int mode = HIBERNATION_INVALID;
927 p = memchr(buf, '\n', n);
928 len = p ? p - buf : n;
930 lock_system_sleep();
931 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
932 if (len == strlen(hibernation_modes[i])
933 && !strncmp(buf, hibernation_modes[i], len)) {
934 mode = i;
935 break;
938 if (mode != HIBERNATION_INVALID) {
939 switch (mode) {
940 case HIBERNATION_SHUTDOWN:
941 case HIBERNATION_REBOOT:
942 #ifdef CONFIG_SUSPEND
943 case HIBERNATION_SUSPEND:
944 #endif
945 hibernation_mode = mode;
946 break;
947 case HIBERNATION_PLATFORM:
948 if (hibernation_ops)
949 hibernation_mode = mode;
950 else
951 error = -EINVAL;
953 } else
954 error = -EINVAL;
956 if (!error)
957 pr_debug("PM: Hibernation mode set to '%s'\n",
958 hibernation_modes[mode]);
959 unlock_system_sleep();
960 return error ? error : n;
963 power_attr(disk);
965 static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr,
966 char *buf)
968 return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device),
969 MINOR(swsusp_resume_device));
972 static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,
973 const char *buf, size_t n)
975 unsigned int maj, min;
976 dev_t res;
977 int ret = -EINVAL;
979 if (sscanf(buf, "%u:%u", &maj, &min) != 2)
980 goto out;
982 res = MKDEV(maj,min);
983 if (maj != MAJOR(res) || min != MINOR(res))
984 goto out;
986 lock_system_sleep();
987 swsusp_resume_device = res;
988 unlock_system_sleep();
989 printk(KERN_INFO "PM: Starting manual resume from disk\n");
990 noresume = 0;
991 software_resume();
992 ret = n;
993 out:
994 return ret;
997 power_attr(resume);
999 static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr,
1000 char *buf)
1002 return sprintf(buf, "%lu\n", image_size);
1005 static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *attr,
1006 const char *buf, size_t n)
1008 unsigned long size;
1010 if (sscanf(buf, "%lu", &size) == 1) {
1011 image_size = size;
1012 return n;
1015 return -EINVAL;
1018 power_attr(image_size);
1020 static ssize_t reserved_size_show(struct kobject *kobj,
1021 struct kobj_attribute *attr, char *buf)
1023 return sprintf(buf, "%lu\n", reserved_size);
1026 static ssize_t reserved_size_store(struct kobject *kobj,
1027 struct kobj_attribute *attr,
1028 const char *buf, size_t n)
1030 unsigned long size;
1032 if (sscanf(buf, "%lu", &size) == 1) {
1033 reserved_size = size;
1034 return n;
1037 return -EINVAL;
1040 power_attr(reserved_size);
1042 static struct attribute * g[] = {
1043 &disk_attr.attr,
1044 &resume_attr.attr,
1045 &image_size_attr.attr,
1046 &reserved_size_attr.attr,
1047 NULL,
1051 static struct attribute_group attr_group = {
1052 .attrs = g,
1056 static int __init pm_disk_init(void)
1058 return sysfs_create_group(power_kobj, &attr_group);
1061 core_initcall(pm_disk_init);
1064 static int __init resume_setup(char *str)
1066 if (noresume)
1067 return 1;
1069 strncpy( resume_file, str, 255 );
1070 return 1;
1073 static int __init resume_offset_setup(char *str)
1075 unsigned long long offset;
1077 if (noresume)
1078 return 1;
1080 if (sscanf(str, "%llu", &offset) == 1)
1081 swsusp_resume_block = offset;
1083 return 1;
1086 static int __init hibernate_setup(char *str)
1088 if (!strncmp(str, "noresume", 8))
1089 noresume = 1;
1090 else if (!strncmp(str, "nocompress", 10))
1091 nocompress = 1;
1092 return 1;
1095 static int __init noresume_setup(char *str)
1097 noresume = 1;
1098 return 1;
1101 static int __init resumewait_setup(char *str)
1103 resume_wait = 1;
1104 return 1;
1107 static int __init resumedelay_setup(char *str)
1109 resume_delay = simple_strtoul(str, NULL, 0);
1110 return 1;
1113 __setup("noresume", noresume_setup);
1114 __setup("resume_offset=", resume_offset_setup);
1115 __setup("resume=", resume_setup);
1116 __setup("hibernate=", hibernate_setup);
1117 __setup("resumewait", resumewait_setup);
1118 __setup("resumedelay=", resumedelay_setup);